This patch addresses bug 14678 by fixing two problems in medium code model

code generation.  Variables addressed through a GlobalAlias were not being
handled, and variables with available_externally linkage were treated
incorrectly.  The patch contains two new tests to verify the correct code
generation for these cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171778 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 3 deletions

diff --git a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index 9ac0a2731a..762b3467c3 100644
--- a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -25,6 +25,7 @@
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalValue.h"
 #include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/GlobalAlias.h"
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -1296,14 +1297,18 @@ SDNode *PPCDAGToDAGISel::Select(SDNode *N) {
 
     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(GA)) {
       const GlobalValue *GValue = G->getGlobal();
-      const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GValue);
-      assert((GVar || isa<Function>(GValue)) &&
+      const GlobalAlias *GAlias = dyn_cast<GlobalAlias>(GValue);
+      const GlobalValue *RealGValue = GAlias ?
+        GAlias->resolveAliasedGlobal(false) : GValue;
+      const GlobalVariable *GVar = dyn_cast<GlobalVariable>(RealGValue);
+      assert((GVar || isa<Function>(RealGValue)) &&
              "Unexpected global value subclass!");
 
       // An external variable is one without an initializer.  For these,
       // for variables with common linkage, and for Functions, generate
       // the LDtocL form.
-      if (!GVar || !GVar->hasInitializer() || GValue->hasCommonLinkage())
+      if (!GVar || !GVar->hasInitializer() || RealGValue->hasCommonLinkage() ||
+          RealGValue->hasAvailableExternallyLinkage())
         return CurDAG->getMachineNode(PPC::LDtocL, dl, MVT::i64, GA,
                                       SDValue(Tmp, 0));
     }